The present disclosure relates to an energy storage system and a synchronization method thereof, and particularly, to an energy storage system for synchronizing a control time between a plurality of slave power controller and a synchronization method thereof.
With the development of industry, the power demand is increased and as a load gap between day and night and a power usage gap between seasons and holidays are increased gradually, the decline of a load factor is intensified.
Recently, for this reason, various load management techniques for reducing a peak load by using surplus electric power are developed and representative one among such techniques is a battery energy storage system.
The battery energy storage system stores surplus electric power at night or surplus electric power generated from wind power and solar light and supplies electric power to a load by discharging the stored electric power during a peak load or a system fault. Through this, it is possible to achieve the maximum load reduction and load leveling. Recently, an emerging smart grid due to the emergence of various new and renewable energy sources may be used for such a battery energy storage system.
On the other hand, an energy storage system may include at least one power controller for controlling discharging or charging energy stored in each load. The power controller may be provided in plurality.
The power controller may include a plurality of slave power controller and one master power controller for controlling operations of each slave power controller.
As a communication method between the master power controller and the plurality of slave power controller, a ring network may be used and a control command transmitted from the master power controller may be sequentially transmitted to the plurality of slave power controller.
In relation to the plurality of slave power controller connected via a ring network, times for receiving control commands transmitted from the master power controller may vary and a time delay may occur in at least one slave power controller.